The station is accessed by 14 entrances, including grand staircases to the west and east, and a sloping passage way on the south. A vaulted ceiling soars 130 feet above the 40,000-square-foot main concourse, which is constantly flowing with people. Their movement is only interrupted by the famous four-faced clock and information booth in the center, often used as a meeting point. The southern facade features another clock with a massive 13-foot diameter, and a statue group by Jules-Felix Coutan, collectively called Transportation. Numerous shops line the corridors, and flanking balconies provide an excellent site from which to view the bustling - yet remarkably hushed - scene. Free tours are provided.

The first building on the site was the Grand Central Depot, completed in 1871. In 1913, it was replaced by the Grand Central Terminal, a Beaux-Arts masterpiece that upgraded the depot with a two-level terminal and third-rail electrification. The $43 million cost was offset by the sale of "air-rights" above the enclosed facility. Penn Central Corporation proposed an office tower to be built over the building in 1968, prompting a public outcry that eventually led to the declaration of Grand Central as a historic landmark.

In 1996, the Metropolitan Transit Authority restoration master plan was approved by the Landmarks Commission. The impressive ceiling of the Main Concourse, with its large constellations mural, was cleaned and restored; the lower concourse restored and converted into a food court; and a second staircase on the east end of the concourse was built to match the one at the west end.